Abstract
Objectives
To determine whether diet influences the metabolism of IV administered allopurinol in healthy dogs.
Animals
6 healthy female Beagles, 4.9 to 5.2 years old and weighing 9.6 to 11.5 kg.
Procedures
Allopurinol was administered IV (10 mg/kg) while dogs consumed a 10.4% protein (dry weight), casein-based diet or a 31.4% (dry weight), meat-based diet. After each dose, plasma samples were obtained at timed intervals, and concentrations of allopurinol and its active metabolite, oxypurinol, were determined by high-performance liquid chromatography. An iterative, nonlinear regression analytical program was used to determine the weighted leastsquares, best-fit curves for plasma allopurinol and oxypurinol concentration-time data. From these data, pharmacokinetic parameters were calculated.
Results
Pharmacokinetic parameters for allopurinol and oxypurinol were not different when comparing the effect of diet.
Conclusion
There is no influence of diet on pharmacokinetic parameters of allopurinol or oxypurinol.
Clinical Relevance
In contrast to observations in human beings, allopurinol metabolism is not influenced by diet. Therefore, formation of xanthine-containing calculi in dogs consuming a high-protein diet and receiving allopurinol is probably not attributable to alteration of allopurinol metabolism. (Am J Vet Res 1997;58:511–515)
